'Ali at-Tamimi was born in 1963 in Washington DC. He grew up at a time when they
were not many Muslims in the Washington DC area.In 1978, when Ali was about 15 years old, his parents moved to Saudi
Arabia. Since 'Ali did not speak Arabic, he attended a private school that was
divided into two sections, Arabic and English.
In Ali’s second year in the School in Riyadh, the school hired a man by the name
of Bilal Philips to teach Islamic Studies in English. This was another turning
point in 'Ali’s life. The young Canadian Bilal Philips was a recent graduate of
the Islamic University in Madinah. Philips — who would later become one of the
most well known Islamic lecturers in the English speaking world — taught his
young students directly from his own university class notes. Philips stressed
the importance of following the Sunnah and not blindly following a personality
or culture. He taught them the importance of supporting any Islamic arguments by
evidences from Qur'an or Hadeeth. In a short period of time, the amount of
knowledge the students amassed was massive. The Canadian teacher shared young
at-Tamimi’s western culture, and now passed on his Islamic knowledge and zeal
for learning to 'Ali.

Being a good and fast reader since childhood, 'Ali read every single book
published about Islam in English (at the time) whether it was by Muslims or
non-Muslims. However, he wanted to learn Islam from the original Arabic sources.
Arabic language became an obstacle for him. Starting with small classical books,
'Ali translated every word with the help of a dictionary. He used to spend the
whole night learning Arabic. Then he started listening to some religious lecture
tapes recorded in Arabic. He would sometimes get the help of some of the Arab
students. Reading an average of six hours per day, he built a strong Arabic
vocabulary. His Arabic improved to a degree that when he applied to Madinah
University later on, he did not need to go through the Arabic program and he
went straight to the college classes.

A book lover, there are about 4,000 books in 'Ali at-Tamimi's personal library.
Most of his lectures and seminars deal with 'Aqeedah (Islamic Creed), amounting
to over 500 hours of recorded audio tapes. He is also a co-author of a widely
distributed Da’wah booklet, “A Brief Illustrated Guide to Understanding Islam.”
The book took a scientific and rational approach to explain Islaam. There are
tens of thousands of people who listened and benefited from 'Ali at-Tamimi's
lectures.